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Human Nutristasis Unit


This section outlines the work of the Human Nutristasis Unit and KEQAS, the vitamin K external quality assurance scheme. KEQAS is a UKNEQAS affiliated external quality assurance scheme.

About the unit

Use the menu on the left to see more information about the unit and detailed information on the full range of diagnostic services it provides.

  • Diagnostic services available

      • Vitamin K1 and vitamin K1 epoxide
      • PIVKA II
      • Warfarin
      • Superwarfarin screen
      • Vitamins A and E
      • Whole blood/plasma Vitamin B6
      • (total) Homocysteine
      • Serum methylmalonic acid
      • Tetrahydrofolate and 5-Methyltetrahydrofolate
      • Active Vitamin B12
      • Vitamin B1
      • Vitamin C
      • 25hydroxy-vitamin D (LC-MS/MS)

    Visit the Viapath website for test information.

  • Clinical advice and expertise

    Advice is available in the following areas:

    • vitamin deficiency/toxicity
    • suspected warfarin resistance
    • suspected warfarin/superwarfarin (rodenticide) poisoning
    • nutrition with respect to homocysteine metabolism

    Please contact the laboratory if you need advice.


Nutristasis Unit
Haemostasis and Thrombosis
4th floor, North Wing
St Thomas' Hospital
Westminster Bridge Road
London SE1 7EH

Diagnostic specimens

Please send diagnostic specimens to the central specimen reception, Viapath, 5th floor, North Wing, St Thomas' Hospital, Westminster Bridge Road, London SE1 7EH.

  • Directions to the unit

    See our travelling to St Thomas' page.

    1. After entering St Thomas' Hospital through the main entrance on the ground floor turn right at the reception desk.
    2. Turn left in to the North wing and take the lift or stairs to the 4th floor.
    3. The Nutristasis Unit is on your left.


Tel: 020 7188 6815